Beer, at its most basic, is a fermented alcoholic beverage made from water and cereal grains. However there are numerous variations on this theme and countless permutations of each variation.
The mineral makeup of water, beer's principal constituent, varies from place to place. This alone means that there is significant regional variation even between beers made with the same recipe.

It is estimated that beer is the third most widely consumed drink in the world, after water and tea, but it is certainly the world's most popular alcoholic beverage. This is not surprising given that beer is much simpler to make than wine or distilled beverages.
Moreover, grape vines are not only harder to manage than cereal crops, they require several years to mature to fruit-bearing age and the fruit needs to be picked before they are ready for fermentation. Cereal crops, on the other hand, are relatively simple to harvest and can be easily stored as required.
History
Beer production dates back to at least 8000 BC, which coincides with the beginning of agriculture, when humans began moving away from a nomadic existence to settle down in permanent communities. Staying in one place provided a reliable, harvestable supply of grain, but also the time and stability to discover and develop the art of fermentation.
Some of the oldest written texts in existence discuss the intricacies of brewing and beer storage. Beer production seems to be a human endeavor that is almost as ancient as agriculture and writing.
People were making beer for thousands of years before they had any real understanding of the vital role of yeast in the fermentation process – beers were left to begin their fermentation naturally, with ambient yeasts. It was only after this single-cell organism was scientifically recognized in the 17th Century that people learned to control and cultivate it – an advance that has helped brewers as well as winemakers and bakers.
Hops
The flowers of the hop vine (Humulus lupulus), commonly known as "hops" are the most common fourth ingredient. These herbaceous vines (a close relative of Cannabis sativa) has been cultivated for many centuries, almost exclusively for beer production.
Hops perform two key functions in beer production: flavoring and preserving. The hop flower contains natural alpha acids with stabilizing and mild antibiotic properties and also beta acids that are responsible for the trademark "hoppy" bitterness. Hops constitute a key differentiating factor between beer styles.
Ale versus lager
Beer can be broadly divided into two basic categories: ales and lagers. The key difference between these two is that ales use top-fermenting yeasts (Saccharomyces cerevisiae), while lagers use bottom-fermenting yeasts (Saccharomyces pastorianus).
Top-fermenting yeasts operate at a temperature of roughly 70F (21C) and form a foam on top of the fermenting liquid. Bottom-fermenting yeasts perform at the much cooler temperature of around 50F (10C).
The majority of beer produced in the world today is lager. The name lager is ultimately derived from the German verb lagern ("to store") referring to the long-term storage of beer in cool locations such as deep cellars or caves. Lagers are typically lighter in color and flavor than ales, and are best served chilled.
Ales are fruitier and more aromatically pronounced than lagers. The precise aromas and flavors are dictated by the quantity and variety of hops added, the type of cereal and the quantity of malted cereals (malt) used.
Whether or not the malt or grains are roasted is also an important factor. Stout and porter beers gain their distinctive dark color and tangy flavor from roasted barley or roasted malt.
Food matches for beer include:
- Moules-frites (mussels with fries)
- Angus beef hamburger
- Beer-battered fish & chips